The homology of Solanum verrucosum and S. commersonii chromosomes revealed by meiosis

چکیده مقاله

The homology of Solanum verrucosum and S.
commersonii chromosomes revealed by meiosis
Submission ID: _O5077
Authors : Jaber Panahandeh *
:University Of Tabriz, Faculty Of Agriculture, Dept. Of Horticultural Science
*: panahandeh@tabrizu.ac.ir
Presentation Type: Sözlü Sunum
Keywords: chromosom pairing,meiosis,laggard chromosome,spindle orientation,potato,solanum commersonii
Abstract:
The commercial potato (Solanum tuberosum) has many wild relatives that are source of genetic diversity and many useful genes for improving the potato tolerance to biotic and abiotic stresses as well as its qualitative traits. But unfortunately using some of them due to the genomic and ploidy difference, different EBN number and pollen pistil incompatibility in potato breeding are limited. One of the most suitable candidate diploid species for potato breeding is S. commersonii. However due to the above mentioned reasons, they are not cross compatible with cultivated potato and considered as tertiary potato gene pool. It is postulated that another wild diploid potato (Solanum verrucosum) could be used as a bridge for transferring the germplasm of wild species such as S. commersonii to the cultivated potato gene pool. In this study, we analysed the meiotic
chromosomal behaviour in a few rare diploid S. verrucosum × S. commersonii hybrids. The results indicated a complete homology between the S. verrucosum and S. commersonii genome showing regular 12 bivalent in the first metaphase of meiosis. The regular metaphasic pairing continued by regular anaphase I with less than 2% of anaphase with laggard chromosome or chromatid bridge. The second meiotic division were also regular again with less than 2 precent of laggard chromosome. In metaphase II, the spindle orientation were parallel or perpendicular, but both of them resulted in four nuclei in tellophase II as well as four spores in sporad stage, while there was no evidence for parallel spindle leading to the unreduced gamete formation. The applicability
of S. commersonii in potato breeding has also been discussed.